/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package com.googlecode.bluetools.dom4j.rule;

import java.util.HashMap;

import com.googlecode.bluetools.dom4j.Document;
import com.googlecode.bluetools.dom4j.Element;
import com.googlecode.bluetools.dom4j.Node;
import com.googlecode.bluetools.dom4j.rule.pattern.NodeTypePattern;

/**
 * <p>
 * <code>RuleManager</code> manages a set of rules such that a rule can be found for a given DOM4J Node using the XSLT
 * processing model.
 * </p>
 * 
 * @author <a href="mailto:james.strachan@metastuff.com">James Strachan </a>
 * @version $Revision: 1.1 $
 */
public class RuleManager {
	/** Map of modes indexed by mode */
	private HashMap modes = new HashMap();

	/**
	 * A counter so that rules can be ordered by the order in which they were added to the rule base
	 */
	private int appearenceCount;

	/** Holds value of property valueOfAction. */
	private Action valueOfAction;

	public RuleManager() {
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @param modeName DOCUMENT ME!
	 * 
	 * @return the Mode instance for the given mode name. If one does not exist then it will be created.
	 */
	public Mode getMode(String modeName) {
		Mode mode = (Mode) modes.get(modeName);

		if (mode == null) {
			mode = createMode();
			modes.put(modeName, mode);
		}

		return mode;
	}

	public void addRule(Rule rule) {
		rule.setAppearenceCount(++appearenceCount);

		Mode mode = getMode(rule.getMode());
		Rule[] childRules = rule.getUnionRules();

		if (childRules != null) {
			for (int i = 0, size = childRules.length; i < size; i++) {
				mode.addRule(childRules[i]);
			}
		}
		else {
			mode.addRule(rule);
		}
	}

	public void removeRule(Rule rule) {
		Mode mode = getMode(rule.getMode());
		Rule[] childRules = rule.getUnionRules();

		if (childRules != null) {
			for (int i = 0, size = childRules.length; i < size; i++) {
				mode.removeRule(childRules[i]);
			}
		}
		else {
			mode.removeRule(rule);
		}
	}

	/**
	 * Performs an XSLT processing model match for the rule which matches the given Node the best.
	 * 
	 * @param modeName is the name of the mode associated with the rule if any
	 * @param node is the DOM4J Node to match against
	 * 
	 * @return the matching Rule or no rule if none matched
	 */
	public Rule getMatchingRule(String modeName, Node node) {
		Mode mode = (Mode) modes.get(modeName);

		if (mode != null) {
			return mode.getMatchingRule(node);
		}
		else {
			System.out.println("Warning: No Mode for mode: " + mode);

			return null;
		}
	}

	public void clear() {
		modes.clear();
		appearenceCount = 0;
	}

	// Properties
	// -------------------------------------------------------------------------

	/**
	 * DOCUMENT ME!
	 * 
	 * @return the default value-of action which is used in the default rules for the pattern "text()|&#64;"
	 */
	public Action getValueOfAction() {
		return valueOfAction;
	}

	/**
	 * Sets the default value-of action which is used in the default rules for the pattern "text()|&#64;"
	 * 
	 * @param valueOfAction DOCUMENT ME!
	 */
	public void setValueOfAction(Action valueOfAction) {
		this.valueOfAction = valueOfAction;
	}

	// Implementation methods
	// -------------------------------------------------------------------------

	/**
	 * A factory method to return a new {@link Mode}instance which should add the necessary default rules
	 * 
	 * @return DOCUMENT ME!
	 */
	protected Mode createMode() {
		Mode mode = new Mode();
		addDefaultRules(mode);

		return mode;
	}

	/**
	 * Adds the default stylesheet rules to the given {@link Mode}instance
	 * 
	 * @param mode DOCUMENT ME!
	 */
	protected void addDefaultRules(final Mode mode) {
		// add an apply templates rule
		Action applyTemplates = new Action() {
			public void run(Node node) throws Exception {
				if (node instanceof Element) {
					mode.applyTemplates((Element) node);
				}
				else if (node instanceof Document) {
					mode.applyTemplates((Document) node);
				}
			}
		};

		Action valueOf = getValueOfAction();

		addDefaultRule(mode, NodeTypePattern.ANY_DOCUMENT, applyTemplates);
		addDefaultRule(mode, NodeTypePattern.ANY_ELEMENT, applyTemplates);

		if (valueOf != null) {
			addDefaultRule(mode, NodeTypePattern.ANY_ATTRIBUTE, valueOf);
			addDefaultRule(mode, NodeTypePattern.ANY_TEXT, valueOf);
		}
	}

	protected void addDefaultRule(Mode mode, Pattern pattern, Action action) {
		Rule rule = createDefaultRule(pattern, action);
		mode.addRule(rule);
	}

	protected Rule createDefaultRule(Pattern pattern, Action action) {
		Rule rule = new Rule(pattern, action);
		rule.setImportPrecedence(-1);

		return rule;
	}
}

/*
 * Redistribution and use of this software and associated documentation ("Software"), with or without modification, are
 * permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions must also contain a
 * copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived from this Software without prior written
 * permission of MetaStuff, Ltd. For written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may "DOM4J" appear in their names without prior
 * written permission of MetaStuff, Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
